#include <stdio.h>
#include <string.h>

int main(void) {
    while (1) {
        int letters[26];
        memset(letters, 0, 26 * sizeof(int));
        int read = 0;
        int c;
        while(c = getchar(), c != '\n' && c != EOF) {
            if (c >= 'a' && c <= 'z') {
                letters[c - 'a']++;
                read++;
            }
        }
        if (read == 0) {
            break;
        }
        int center = 0;
        for (int i = 0; i < 26; i++) {
            if (letters[i] % 2 != 0) {
                // BREAKPOINT BELOW
                if (center != 0) {
                    puts("No");
                    goto next;
                } else {
                    center = 1;
                }
            }
        }
        puts("Yes");
        next:
        if (c == EOF) {
            break;
        }
    }
    return 0;
}
